ra_serf: partially revert r34179 but ignore cert chains with serf 0.3.0+.
ra_serf: partially revert r34179 but ignore cert chains with serf 0.3.0+.

* subversion/libsvn_ra_serf/util.c
  (ssl_server_cert): If we're using serf 0.3.0+, implicitly approve non-server
  certs; allow certificate storage to be corrupted again (only with serf
  <0.3.0).


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@874829 13f79535-47bb-0310-9956-ffa450edef68

YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion